Fix failing test in Glm4vMoeIntegrationTest

[Sai-Suraj-27]

What does this PR do?

Fixes these failing tests in Glm4vMoeIntegrationTest.

As discussed here, It depends on how pytest collects the different tests, so similar to Lfm2MoeIntegrationTest, Qwen3MoeIntegrationTest (which are not failing in their get_model() function calls with this issue) it would be ideal to have setUpClass that initializes cls.model always.

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

Who can review?

@ydshieh @Cyrilvallez

[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: glm4v_moe

[ydshieh]

Thank you @Sai-Suraj-27 I will take a closer look.